Heater



Patented Aug. 25, 1936 UNITED STATES PATENT OFFIQE HEATER Application August 14, 1933, Serial No. 685,052

1 Claim.

The invention relates generally to heaters and more particularly to a radiant heater especially adapted for use where the application of heat of relatively low intensity but uniformly over a large area is desirable, as for example in treating nut products and the like while on display for sale.

The general object of the invention is to provide an electric heater for the purpose above indicated, constructed to radiate heat uniformly along an elongated relatively narrow area and which is capable of economical operation.

Another object of the invention is to provide a heater having a reflector adapted for use with a heating element of small diameter and yet capable of effecting a substantially uniform distribution of radiant heat over a narrow area of substantial length.

A further object is to provide a heater of the above character which is adapted to be mounted easily and conveniently on the top plate of a display case or other support.

i Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawing, in

which:

Figure 1 is an enlarged sectional View taken on the line ll of Fig. 2 of a heater embodying the features of the invention.

Fig. 2 is an elevational view of the heater.

Fig. 3 is a perspective view of a modified form of heater.

In the present preferred embodiment of the invention, the heater comprises generally an elongated reflector, and a heating element of small diameter within the reflector, cooperating with the reflector to effect the uniform distribution of the heat over an elongated surface area. In the drawing, [0 designates generally the elongated reflector. It is made of sheet metal and shaped to provide a main trough-like body ll of parabolic cross-section preferably uniform throughout its length and at longitudinally spaced points in the body Ill are secured transverse plates l2 providing plane reflecting surfaces. Centrally of the reflector thus formed is an electric heating element l3.

The heating element I3 is disposed midway between the plates l2. Preferably it is of a wellknown standard form frusto conical in form and is supported by a socket l 4 extending through and attached to the reflector body I I at the vertex of the parabola. The heating element is thus positioned on the axis of the parabola, and the smaller end of the conical member is nearer the vertex of the parabola so that the heat from the heating element will be radiated upwardly and outwardly toward all parts of the reflector.

The plates l2, it will be observed, are spaced longitudinally from the heating element and serve to limit the longitudinal reflection of heat. To 5 provide ventilation, the plates l2 may be apertured by cutting slots I6 in the edges thereof adjacent the inner surface of the body II.

For convenience in mounting the heater on the top plate of a display case or on some other sup- 10 port, it is provided with spaced attaching means each comprising a rod 20 having its lower end threaded and extending through the reflector body II at one end thereof, a nut 2| and a pair of washers 22 being placed on the end of the rod 15 to clamp the reflector body I I therebetween. The outer end of the rod 20 is also threaded and a pair of laterally extending clamping members 23 are placed thereon with a spacing washer 24 therebetween, a nut 25 securing the whole together. 20 Spaced from the rod 20 is a clamping screw 26 extending through the two members 23 for clamping them on a fixed support such as the top plate 21 of a glass show case, the screw 26 abutting the edge of the glass to locate the heater. 25

In order that the device may attract attention when used in retail trade, the reflector [0, which normally hides the heating element from view, is provided with an aperture 28 in one wall thereof directly opposite the heating element I3. Thus, 30 the glow from the heating element may be seen through the aperture 28 to attract attention.

The modified form of heater shown in Fig. 3 is constructed for use where it is desired to heat a very long narrow area. This form of device comprises a substantially parabolic reflector body 30 within which are placed a plurality of longitudinally spaced heating elements 3| disposed between spaced plates 34.

In the operation of the heater, heat is radiated to all parts of the inside surface of the elongated reflector [0 which reflects the heat outwardly from the parabola. The rays of heat reaching the ends of the reflector H] are reflected by the 45 end reflectors l2 toward the surface of the reflector l0.

It has been found that with the construction thus provided, heat is reflected with substantial uniformity over a large area similar in shape to 50 the open side of the reflector body without any substantially greater intensity at the center of such area adjacent the heating element l3 than in other parts of such area. Accordingly the heater is especially well adapted for use in ap- 55 plying heat of relatively low intensity economically over a large area.

I claim as my invention: A radiant heater comprising an elongated 5 transversely curved trough-like reflector having end pieces, the edges of the end pieces adjacent the reflector having ventilating slots, and an electrical heating element of the standard conical form located within the curve of the reflector with its axis at substantially a right angle to the longitudinal axis of the reflector, one side of the reflector having a sight opening opposite the heating element.

LESTER M. SAWIN. 

